1. Field of the Invention
The present invention relates to a vehicle assembling method in which an upper body shell and lower body shell are assembled separately and thereafter the lower body shell is moved to the upper body shell to be combined with the upper body shell.
2. Description of the Related
Generally, a conventional vehicle assembling process includes a pressing process in which a steel plate is processed, a body assembling process in which the body shell is assembled, an application process in which coating material is applied on the vehicle body surface, and an equipping process in which various fit-in parts are equipped for vehicle structure. Conventionally, an underbody portion including a floor member, a front body portion, a rear body portion, a body side panel, roof member and the like is sub-assembled in order to form a body shell. Thereafter, the equipping process is applied on the body. It should, however, be noted that it is difficult to automate the equipping process because the assembled body shell will hinder the equipping operation. In view of this, it has been proposed that a vehicle assembling process can be done efficiently by being automated as much as possible.
For example, Japanese Patent Public Disclosure No. 63-235174, laid open to the public in 1988, discloses a vehicle assembling process including steps of assembling the front body portion defining an engine room, an under body portion including the front floor and center floor and rear floor, an upper body shell including a body side panel and a roof member, fit-in parts, assembling the under body portion and front body portion to form lower body shell, and mounting the upper body shell on the lower body shell.
In Japanese Utility Model Public Disclosure No. 64-28377, there is disclosed a vehicle assembling process including steps of assembling lower body shell, including a front body portion and an under body portion, and an upper body shell including a body side panel, a roof member and cowl member, equipping these body panels, and joining the upper body shell with the lower body shell. Meanwhile, the upper body shell is formed with a side sill upper and the lower body shell is formed with a side sill lower. When the upper side sill upper and the side sill lower are combined, a whole side sill structure is formed.
In the above assembling techniques, the floor member is formed at side ends with a downwardly extending flange portion which is joined with a flange of the side sill by a plurality of bolts. It is, however, to be noted that joining the floor member with the side sill is not easy because a plurality of openings for inserting the bolts must align with each other. Another reason is that as manufacturing error of the floor member and the upper body shell increases, the flange portion of the floor panel is more difficult to be fitted with the flange of the side sill. As a result, it becomes difficult to combine the floor panel and the side sill. Otherwise, the joint of the floor panel and the side sill is less reliable.
In the assembling technique as disclosed in the Japanese Patent Public Disclosure No. 64-28377, it is necessary to join horizontal flanges of a side sill upper and lower when the upper body shell is combined with the lower body shell. It should be, however, noted that it is difficult to join the horizontal flanges of the side sills where the upper and lower body shell are not processed accurately. If they are joined by welding, coating of the body shell would be injured. The body shells cannot be smoothly joined by an automatic assembling method because of manufacturing error.